Distribution panel



y 1939- w. H. FRANK ET AL 2,158,658

DISTRIBUTION PANEL LFil'ed April 15, 1935 4 Sheets-Sheet l E 7 INVENTOR} ATTORNEY.

May 16, 1939- w. H. FRANK ET AL DISTRIBUTION PANEL Filed April 15, 1935 4 Sheets-Sheet 2 til N M Y O E m w m v m 5 z M 5 T A 5 B Z 7\ 5 id 0 flv u W M Aw EQIW lam? y 1939- w. H. FRANK .ET AL 2,158,658

DISTRIBUTION PANEL Filed April 15, 1935 4 Sheets-Sheet 3 ATTORNEY.

y 1939- w. H. FRANK El" AL 2,158,658

DISTRIBUTION PANEL Filed April 15, 1935 4 Sheets-Sheet 4 Patented May 16, 1939 UNITED STATES PATENT OFFICE DISTRIBUTION PANEL Application April 15,

11 Claims.

This application relates to distribution panels.

It is common practice in the art of panelboard construction to make the panel of units so that the panelboards are of the sectional type, and the panelboard here shown follows this practice. The panelboard here shown, however, differs from sectional panelboards heretofore known in details of construction of the units per se, in details of construction of the circuit control parts, namely the switches, which form parts of the units, in details of mounting the units in the panelboard as a whole, and other details of construction.

The principal object of the invention is to simpli'fy and minimize the expense of the manufacture and installation of panelboards and parts by providing novel details of construction and design of such panelboards and parts.

One feature of design is the construction of a sectional panelboard unit composed largely of molded insulation and having a front surface composed largely of a metal plate or cover which closes two large openings formed to extend through the units from front to back thereof, and mounts the several switches which are disposed in these openings. Screws hold the covers in place in front of the units, and thread into the cabinet so as to hold the units in place in the cabinet. Consequently, the screws referred to may be considered as a means for supporting the assembly of several switches with respect to the cabinet or tub, as a means for supporting the unitswith respect to the cabinet, and as a means for supporting the asembly of several switches with respect to the units.

Since the screws thread into the cabinet, each unit is found to be clamped by and betweenv two fiat metal plates of large area, one being the cover and the other being the back of the cabinet. This reinforces the units and mounts them without imposing any undue stress on the units themselves.

An important feature is the grounding of the front of the panel through the screws. The covers are grounded to the cabinet through the screws, and the switch handles are grounded to the covers.

Another important feature is the multiple functioning of many parts. The multiple functioning of the screws aforesaid has been described. Other screws also have multiple functions: for example, one screw holds a fuse shell in place, forms a tip contact, and electrically and physically connects and mounts a contact strap; another screw electrically connects and physically mounts a bus bar and a contact strap. The

1935, Serial No. 16,330

screws that mount and ground the cover plates, the units, and the switches also reinforce the units and help provide backings against switch action.

Other important features relate to new and improved switches and switch details particularly adapted for use in connection with panelboards of the type here shown, and such details will later be described, it being observed that such switches are of the type shown in application Ser. No. 723,052, April 30, 1934, now abandoned and replaced by application Serial No. 56,229, filed December 26, 1935.

Still further objects of the invention will readily occur to those skilled in the art upon reference to the following description and the accompanying drawings, in which,

Fig. 1 is a front elevation view of a panelboard embodying the invention, the same being shown with a hinge cover thereof in open position, and with the cabinet front partially cut away to expose the neutral bar and the bus bar terminals of the panel;

Figs. 2 and 3 are sections as. if on lines 2-2 and 33 of Fig. 1, Fig. 3 not showing the cabinet forming part of the panelboard;

Figs. 4 and 5 are partial sections as if on lines 4-4 and 55 of Fig. 3;

Fig. 6 is a side sectional view of an installed panel, and in this figure there is shown a switch assembly about to be inserted into a mounted unit;

Figs. '7, 8 and 9 are detail sections as if on lines l'-|, 8-8, and 99 of Figs. 1 and 7;

Figs. 10, 11, and 12 show the switch parts in on, "intermediate, and off positions, respectively;

Figs. 13-24, in pairs, show modifications of switch details, diagrammatically, and in on and off" positions;

Figs. 25-28 show further modifications of switch details.

The panelboard here shown includes a sheet metal cabinet or tub I having its back wall H mounted against a surface I2 which supports the panelboard. The front of the cabinet is open but may be closed by a front cover 14 secured thereto by screws l passing through corner lugs of the cabinet and the cover I! supports a hingedly mounted door [6 and a bevel masking plate 11 cooperating with the panel 18 in the cabinet to conceal the wiring gutters l9 and the top and bottom end spaces 19a between the panel and the walls of the cabinet.

On the back ll of the cabinet is a shock or cushioning pad of insulation 20, and against this pad and disposed one above the other are the units H which form the panel 58 of the panelboard.

Each unit 2| comprises a body composed of molded insulation or the like formed to provide top and bottom walls 22, end blocks 23, and a central barrier 24 between which and the end blocks are openings 25 extending from front to back of the unit. The back of each end block 23 is formed with a slot 2'! extending from the top to the bottom wall of the unit, and the slots 2'! of adjacent units align to form continuous channels which run from the top to the bottom of the panel and in which are disposed the main bus bars 28. The channels are lined with fiber insulators 29 so as to be completely shielded.

Each end block 23 is formed with a pair of cavities open to the front of the unit and each cavity is provided with an entrance hole 3! opening to the adjacent end wall of the unit. In each cavity is a socket shell 32 for the reception of a plug fuse and each socket shell has an aperture in line with an entrance hole 3|. Each socket shell contains a tip contact screw 33 and, in addition, a wire connection screw 34 by means of which a branch circuit wire, disposed in the adjacent wiring gutter l9 and introduced into the cavity 30 through the entrance hole 3i of the cavity and through the aligned hole of the socket shell 33 therein, may have its terminal physically and electrically connected to the socket shell. The tip contact screws 33 thread through the end block 23 and into those portions of the stationary contacts 55 which are in the adjacent slot 27.

For the two socket shells there are two of these stationary contacts, and between the pair of stationary contacts 35 of each end block is a second pair of stationary contacts 31, these being mutually connected by an integrally formed plate-like part 38 in back of the end block 23 and in the slot 2i. Extending through the end block from front to back of the unit is a counterbored hole 39, and in this hole is a screw 40 which threads through the plate 38 and into the bus bar 28 behind the unit, the head of the screw being accessible, though not accidentally, from the front of the unit, and the screw functioning to electrically c011- nect the stationary contacts 3'! to the bus bar and also cooperating to support the bus bar with respect to the unit.

The contacts 36 and 3'! have portions (Fig.4) extending forwardly from the back of the end block 23, and these portions are disposed in the openings 25 on walls of the end blocks. For cooperating with these portions of the contacts 3E-3l are U-shaped bridging contacts resiliently mounted on a contact carrier referenced as a whole 41, one of whose ends is fulcrumed at 48 in the portion 49 of a strap 5i] which forms part of the switch assembly. The other end of the carrier 4'! is pivotally connected at 5! to a lever 52 which fulcrumed at 53 to an assembly or front plate 54 fixedly connected to the portion 55 of the strap 50, and the lever 52 has an exposed handle end 56 whereby it may be moved on its fulcrum 53 for switching action.

In the unit shown there are four branch circuit plug fuse socket shells 32 and consequently there are four single pole switches assembled in a gang on the one assembly plate 54, each switch including a lever 52, a carrier 41, and a U-shaped movable contact 46.

The four switches together with the assembly plate 5 5 constitute a switch assembly which may be associated with a unit as a whole in a manner shown best in Fig. 6, and when so assembled the switch assembly may be supported by means of screws 58 which pass through holes 59 of the central barrier wall 24 of the unit and thread into the back wall 5 i of the cabinet or tub Hi.

It is here observed that the screws 58 electrically interconnect the cabinet and the plate 54, and the switch levers or handles; consequently, if the cabinet is grounded, in accordance with good practice, the front of the panel, including plate 54 and the handles, is also grounded.

It is also observed that each unit is reinforced by the provision of plate 55 which covers the front thereof, and that each unit is clamped between a front plate and the cabinet back, both of large area.

At one end of the panel, namely at the lower end in the installation shown, a pair of insulation blocks lfl are fixedly mounted against the back of the panel as by means of the screws 1 I, and these blocks form pedestals for a neutral bar l2 which connects them and which is mounted thereon as by means of the screws '53. The neutral bar is provided with a plurality of binding screws 14, as is conventional in neutral bar construction, and is shielded in accordance with good electrical practice by means of an insulation shield 75 (Fig. 8) in front of the neutral bar and held thereon in the manner shown by the screws 13.

At the opposite end of the panel, namely the upper end in the panel shown, the terminals of the bus bars which extend above the uppermost unit are provided with connecting lugs 85, by means of which main feed cables may be electrically connected to the bus bars 28, and for bracing the bus bars at these free ends, pedestals 8i similar to those used for the neutral bar are employed. An insulation shield 82 similar to that employed for the neutral bar is employed in conjunction with these pedestals 8i and the terminals of the bus bars,

The lugs 8% are hollow metal cups provided with integral shanks 83 riveted in the bus bars and containing set screws 84 for clamping in the cups cable terminals threaded into the cups through the aligned apertures 85.

While many of the details of construction of the switches per se have been adequately disclosed in application Serial No. 723,052, filed April 30, 1934 in the names of William H. Frank and Joseph Messing, and abandoned and replaced by application Serial No. 56,229, filed December 26, 1935, a specific description of the switches will here be given.

In the switch here shown the handle portion 56 is given the shape shown best in Figs. 1 and 2 and alternately presents to front view two surfaces, one of which is marked on and the other of which is marked and such markings indicate the condition of the switch.

The contact 46 has a heel 12a which normally is in contact with the stationary contact 36 or ill, and a toe 351) which provides an arcing tip, and is resiliently and loosely mounted, as by means of an insulated metal rivet Ma and a cone spring 'ib, on the carrier which is generally formed as a flat resilient member (Figs. 10-12, 2526), insulators llc being utilized to insulate the rivet and the spring from the carrier, generally made of conducting material.

The part which mounts the cover plate 54 and the switches has resilient cut out lugs or tongues a which form resilient stops or limits for the movement of the ends 5! of the switch handles to foff position, and the position of the hus'may be. varied manually to adiustably determine the "off position of the handles.

While parts 49 are resiliently mounted with respect tothe unit by their own resilience and thus furnish a. degree of resilience to the mountings or iulcnuns of the switch springs 41. parts 50 as a whole are rigidly backed by their engagement with wall ll of the unit which in turnls reinforced by thesorews 58.

Switch actions When theswitch is in on position, the expanding tendency of the carrier and the ful-. cruming of the parts at 48-53, and the restraint against further movement of lever 52 (clockwise-Fig. 10) cooperate to look the heel 4611 against the stationary contact with a positive pressure or toggle action lock, heel 460 being at the pressure or knee point of the toggle whose ends are fixed against movement.

When the lever 52 is moved towards the position (Fig. 12), the carrier first contracts and bows towards contact 36 as shown by dotted lines of Fig. 10, maintaining contact pressure until after lever 52 has passed the intermediate over center position (Fig. 11), whereupon it expands with a snap action to pull contact 46 away from the stationary contact, toe 46b remaining in contact until long after lever 52 has passed over center and long after heel 46a has broken contact, the arcing for break being at tip or toe 46b. In "off position, the parts are locked at restby the expanding tendency of the carrier and by the engagement of lever point 5| with the fixed strap 50 which fixes the upper end of carrier 41, the lower end thereof being fixedat its fulcrum 48.

Various switch actions may well be attained by the use of differently formed carriers, such a diversity of formations being possible only because the actuating spring shown is of the flat or bow type. The carrier HII of Figs. 13-14 provides a fast and heavy snap. On and off timing that are equal, and a fair degree of contact pressure; the carrier I02 provides a medium snap action, on and off" timing that are equal, and light contact pressure; the carrier I03 provides a light snap action, a faster off movement than its on movement, and light contact pressure; the carrier I04 resembles the carrier 803 but provides a heavier contact pressure; the carriers Hi5 and H16 are reinforced by springs of which I0! is a leaf spring and I is a coil spring; and the end of carrier I06 rides in a wide seat of its handle, as contrasted with the narrow seats for the other carriers.

Figs. 25-26 show how flexing and bend points may be determined by providing on carriers "9-4 W notches HI-I l2; and Figs. 27-28 show with carriers H3 the use of brushes H4, single or double.

Other details of construction relating to barriers, anticreepage surfaces, etc., are not specificallydescribed, the provision of these being within the range of one skilled in the art of panelboard design.

Now having described the panelboard here shown and its details of construction, reference will be had to the claims which follow for a determination of the scope of the monopoly claimed.

We claim:

1. A switch unit comprising a block of molded insulation having large cavities open to the front of the unit, stationary switch contacts on interior walls of the cavities, and a unitary'mask and switch assembly mountable thereon and removable therefrom from the front thereof and as a unit, and comprising a large area masking plate in front of the unit and closing the cavities, and

switches fixedly mounted on and carried by and behind the plate and disposed in the cavities and having handles projecting through openings in the plate and manipulable to cause movable contacts of the switches to engage the stationary contacts, and means in the nature of a screw or the like accessible from in front of the plate for mounting the plate on and in front of the unit, the screw passing through a portion of the unit. forming a barrier between the cavities and threading into a wall part behind the unit whereby the unit is clamped and mounted by and between its front plate and the wall part.

2. A switch unit comprising a block of molded insulation having large cavities open to the front of the unit, stationary switch contacts on interior walls of the cavities, and a unitary mask and switch assembly mountable thereon and removable therefrom from the front thereof and as a unit, and comprising a large area masking plate in front of the unit and closing the cavities, and switches fixedly mounted on and carried by and behind the plate and disposed in the cavities and having handles projecting through openings in the plate and manipulable to cause movable contacts of the switches to engage the stationary contacts, and means in the nature of a screw or the like accessible from in front of the plate for mounting the plate on and in front of the unit, the screw passing through a portion of the unit forming a barrier between the cavities and threading into a wall part behind the unit whereby the unit is clamped and mounted by and between its front plate and the wall part, the masking plate being of metal or the like and electrically connected to the wall part by the screw.

3. A switchblock having bus bars near and extending along opposed ends thereof, said block having at each end-two branch leads entering the block, a set of two stationary switch contacts connected to the terminals of said leads, a set of two other stationary switch contacts connected to each other and to the bus bar, and two movable switch contacts, each connecting a stationary contact of one set to a stationary contact of the other set, the sets of stationary contacts being arranged and spaced in a line running in the direction of the bus bar, a cavity receiving said movable contacts and the switch mechanism of which the movable contact is a part, said block also having a center wall separating said cavities, and means passing through the center wall for mounting the four switch mechanisms in the cavities.

4. A switchblock having bus bars near and extending along opposed ends thereof, said block having at each endtwo branch leads entering the block, a set of two stationary switch contacts connected to the terminals of said leads, a set of two other stationary switch contacts connected to each other and to the bus bar, and two movable switch contacts, each connecting a stationary contact of one set to a stationary contact of the other set, the sets of stationary contacts being arranged and spaced in a line running in the direction of the bus bar, a cavity receiving said movable contacts and the switch mechanism of which the movable contact is a part, said block also having a center wall separating said cavities, and means passing through the center wall for mounting the four switch mechanisms in the cavities, these four switch mechanisms being formed as a unitary assembly with a single mounting plate which forms a cover for all four cavities.

5. A switchblock having at each enda bus bar near thereto and extending therealong, a branch lead entering the block, a stationary switch contact connected to the branch lead and a. stationary switch contact connected to the bus bar and a movable switch contact for connecting the stationary switch contacts, the stationary switch contacts being arranged and spaced in a line running in the direction of the bus bar, and a cavity receiving said movable contacts and the switch mechanism of which the movable contact is a part, said block also having a center wall separating said cavities, and means passing through the center wall for mounting the two switch mechanisms in the cavities.

6. A switchblock having at each end-a bus bar near thereto and extending therealong, a branch lead entering the block, a stationary switch contact connected to the branch lead and a stationary switch contact connected to the bus bar and a movable switch contact for connecting the stationary switch contacts, the stationary switch contacts being arranged and spaced in a line running in the direction of the bus bar, and a cavity receiving said movable contacts and the switch mechanism of which the movable contact is a part, said block also having a center wall separating said cavities, and means passing through the center wall for mounting the two switch mechanisms in the cavities, these two switch mechanisms being formed as a unitary assembly with a single mounting plate which forms a cover for all four cavities.

'l. A switch unit comprising a block of molded insulation having large cavities open to the front of the. unit, stationary switch contacts on interior walls of the cavities and a unitary mask and switch assembly mountable thereon and removable therefrom from the front thereof and as a unit, and comprising a large area masking plate in front of the unit and closing the cavities, and switches fixedly mounted on and carried by and behind the plate and disposed in the cavities and having handles projecting through openings in the plate and manipulable to cause movable contacts of the switches to engage the stationary contacts, and means in the nature of a screw or the like accessible from in front of the plate for mounting the plate on and in front of the unit, the screw passing through a portion of the unit forming a barrier between the cavities and threading into a wall part behind the unit Whereby the unit is clamped and mounted by and between its front plate. and the wall part, the switches being of the spring pressure type so constructed that circuit closing movements thereof are arrested by engagement of their movable contacts with the wall mounted stationary contacts.

8. A switch unit comprising a block of molded insulation having large cavities open to the front of the unit, stationary switch contacts on interior walls of the cavities and a unitary mask and switch assembly mountable thereon and removable therefrom from the front thereof and as a unit, and comprising a large area masking plate in front of the unit and closing the cavities, and switches fixedly mounted on and carried by and behind the plate and disposed in the cavities and having handles projecting through openings in the plate and manipulable to cause movable contacts of the switches to engage the stationary contacts, and means in the nature of a screw or the like accessible from in front of the plate for mounting the plate on and in front of the unit, the screw passing through a portion of the unit forming a barrier between the cavities and threading into a wall part behind the unit whereby the unit is clamped and mounted by and between its front plate and the wall part, the switches being of the spring pressure type so constructed that circuit closing movements thereof are arrested by engagement of their movable contacts with the wall mounted stationary contacts, and circuit opening movements thereof are arrested by engagement of moving switch parts with walls of the cavities.

9. A switch unit comprising a block of molded insulation having large cavities open to the front of the unit, stationary switch contacts on interior walls of the cavities, and a unitary mask and switch assembly mountable thereon and removable therefrom from the front thereof and as a unit, and comprising a large area masking plate in front of the unit and closing the cavities, and switches fixedly mounted on and carried by and behind the plate and disposed in the cavities and having handles projecting through openings in the plate and manipulable to cause movable contacts of the switches to engage the stationary contacts, and means in the nature of a screw or the like accessible from in front of the plate for mounting the plate on and in front of the unit, the screw passing through a portion of the unit forming a barrier between the cavities and threading into a wall part behind the unit whereby the unit is clamped and mounted by and between its front plate and the wall part, the masking plate being of metal or the like and electrically connected to the wall part by the screw, the switches being of the spring pressure type so constructed that circuit closing movements thereof are arrested by engagement of their movable contacts with the wall mounted stationary contacts.

10. A switch unit comprising a block of molded insulation having large cavities open to the front of the unit, stationary switch contacts on interior walls of the cavities, and a unitary mask and switch assembly mountable thereon and removable therefrom from the front thereof and as a unit, and comprising a large area masking plate in front of the unit and closing the cavities, and

switches fixedly mounted on and carried by and behind the plate and disposed in the cavities and having handles projecting through openings in the plate and manipulable to cause movable contacts of the switches to engage the stationary contacts, and means in the nature of a screw or the like accessible from in front of the plate for mounting the plate on and in front of the unit, the screw passing through a portion of the unit forming a barrier between the cavities and threading into a wall part behind the unit whereby the unit is clamped and mounted by and between its front plate and the wall part, the masking plate being of metal or the like and electrical- 1y connected to the wall part by the screw, and

switches being of the spring pressure type so con structed that circuit closing movements thereof are arrested by engagement of their movable contacts'with the wall mounted stationary con tacts, and circuit opening movements thereof are arrested by engagement of moving switch parts with walls of the cavities.

11. A switch unit comprising a block of insulation having a large cavity open to the front of the unit, a stationary switch contact on the'interior wall of the cavity, and a unitary mask and switch assembly mountable thereon and removable therefrom from the front thereof and as a unit, and comprising a large area masking plate in front of the unit and closing the cavity, and a switch fixedly mounted on and carried by and behind the plate and disposed in the cavity and having a handle projecting through an opening in the plate and manipulable to cause a movable contact of the switch to engage the stationary contact, and means in the nature of a screw or the like accessible from in front of the plate for mounting the plate on and in front of the unit, the screw passing through a portion of the block and threading into a Wall part behind the unit whereby the unit is clamped and mounted by and between the front plate and the wall part, the masking plate being of metal and electrically connected to the wall part by the screw.

WILLIAM H. FRANK.

JOSEPH A. MESSING.

CLARENCE T. HOLLINGSWORTH. 

